## 48.3. Keeping Up with Security Alerts

If you have a Microsoft Windows system, you're probably familiar with the frequent security bulletins from Microsoft's Security division. One of the nice things about Microsoft's security is that you can get security alerts emailed to you so that you're made aware of new vulnerabilities as soon as Microsoft acknowledges them.

In the Unix world, you may have to make a little more effort to keep up with the security alerts for various flavors of Unix; however, keeping up with the alerts isn't a horrendous amount of work. It's just a case of knowing where to look for them.

I've already mentioned CERT (Section 48.2). This web site has some of the best information about new security vulnerabilities, and if you're managing a multiuser Unix system, you should check this site at least once a day. Even if you only have a single-use Unix box, you should check the site frequently. Note, though, that CERT publicizes all security vulnerabilities, not just Unix ones. On the day I wrote this, when I checked at CERT's Advisories page (at http://www.cert.org/advisories/), there were advisories on Oracle, the zlib Compression library, PHP, and Microsoft's Internet Explorer, to name just a few.

If you're running a Linux system, you can check Linux Security at http://www.linuxsecurity.com for up-to-date information on security problems related to Linux operating systems. In addition, you can read articles on Linux security and download security-related utilities. When I accessed the site, the current reported exploit was related to a vulnerability with Apache, and the most current advisory was warning about a potential buffer overflow (Section 48.4) problem related to FreeBSD's squid port.

What I particularly like about Linux Security is that it shows security advisories categorized by flavor of Unix/Linux. Among the categories are Corel, Caldera, Red Hat, Slackware, Debian, FreeBSD, NetBSD, and so on. Since I run a Red Hat Linux box as well as a FreeBSD web server, it is particularly helpful for me to see what I need to be aware of in both of these environments.

O'Reilly publishes information about Unix and open source at the Linux DevCenter at the O'Reilly Network (at http://linux.oreillynet.com). Rather than list all vulnerabilities, this site tends to focus on specific instances and then covers each in more detail than you'll normally get at the other security sites.

-- SP

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